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Sameer Kankute af17400c38
feat(a2a): well-known agent-card discovery + LangGraph Platform mode (#28860)
* feat(a2a): well-known agent-card discovery + LangGraph Platform mode

Adds a registration-time discovery flow so admins can paste an upstream
agent URL, see its skills/capabilities, pick what to expose, and have the
proxy front it with a LiteLLM-shaped agent card.

Backend (new litellm/proxy/a2a/ module):
- fetch_well_known_card walks /.well-known/agent-card.json,
  /.well-known/agent.json, /agent.json by default. langgraph_platform
  mode hits the canonical path with ?assistant_id=<id> (LangGraph
  serves one shared endpoint per deployment).
- merge_agent_card overlays LiteLLM overrides on the upstream card:
  drops upstream url, forces protocolVersion=1.0, replaces
  securitySchemes with LiteLLMKey bearer, emits supportedInterfaces
  pointing at the proxy, filters capabilities to a small allowlist,
  strips non-v1.0 fields.
- POST /v1/a2a/discover returns the raw upstream card (admin-only) so
  the UI can render skills/capabilities for selection.
- create/update/patch agent endpoints pre-generate the agent_id and
  run merge_agent_card before storing, so DB.agent_card_params already
  embeds the proxy-fronted URL.

UI (ui/litellm-dashboard):
- New AgentCardDiscovery component with a parent-driven plan:
  discovery_mode + params + display URL. For LangGraph the parent
  composes (api_base, assistant_id); for pure A2A it uses the url
  field. Component hides the manual URL input when the parent drives.
- add_agent_form wires discovery for every non-custom agent type and
  overlays the user's selections onto agent_card_params at submit,
  fixing the bug where dynamic agent forms ignored discovery picks.

Completion-bridge fixes (paired):
- Add kind: "message" to A2A response messages and unwrap result
  so it's a Message directly per spec (matches a2a SDK
  SendMessageResponse validation).
- Forward A2A metadata to LangGraph runs via extra_body.metadata.

* fix(a2a): preserve agent url, fix streaming chunk envelope, and protect forwarded metadata

- Streaming chunk: move final out of the message object into the
  result envelope per the A2A spec.
- Agent card merge: keep upstream url on the stored card so the
  runtime invocation path can locate the upstream backend; the public
  well-known endpoint already rewrites this field to the proxy URL
  before exposing it to clients.
- Completion bridge: apply A2A forward metadata after merging
  litellm_params so an agent-configured extra_body cannot
  overwrite the forwarded metadata.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): fix legacy streaming chunk, agent card test, and metadata merge

- providers/litellm_completion: move 'final' out of the message object
  into the result envelope per the A2A spec (matches the bridge fix).
- agent endpoints test: the runtime invocation path now preserves the
  top-level 'url' on the stored card, so update the assertion to match.
- completion bridge metadata: when forwarding A2A metadata via
  extra_body.metadata, merge into any existing extra_body.metadata
  instead of replacing it, so an agent-configured metadata block is
  preserved (forward metadata still wins on key conflicts).

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): remove dead duplicate transformation dir; drop SSRF-prone headers field from /v1/a2a/discover

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): revert accidental html→index.html rename from afc8b10f

The commit afc8b10f bundled real A2A fixes alongside an unintended
re-introduction of the */index.html layout that 8513d7fc had already
reverted. Restore all 35 static-export pages back to the flat *.html
structure that matches the upstream main branch.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(a2a): address PR review comments

UI:
- Auto-trigger discovery when connection details are filled; remove
  the "Use these selections" button (selection syncs live to parent,
  user just clicks Next).
- Edit Settings: auto-discover upstream card on open; cross-check with
  DB-stored card so only already-saved skills/capabilities are pre-ticked.
- Extract shared buildDiscoveryRequest + selectionsFromSavedAgentCard
  helpers into agent_discovery_utils.ts so both add and edit flows share
  the same logic.

Backend:
- agent_card.py: rename the proxy security requirements field from the
  non-standard ``securityRequirements`` to the spec-correct ``security``
  key (matches AgentCard TypedDict and A2A/OpenAPI convention).
- agent_card.py: remove ``securityRequirements`` from _ALLOWED_TOP_LEVEL_KEYS.
- endpoints.py: _build_merged_agent_card now forwards agent_name and
  description from the request so the stored card reflects the admin-
  supplied name, not just whatever the upstream card advertised.
- utils.py: remove overly-broad ``or "parts" in result`` fallback; use
  ``kind == "message"`` check only to avoid false matches on future
  result types that happen to include a ``parts`` field.
- test_agent_card.py: update assertions to expect ``security`` key.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix: restore Next.js metadata directories to match upstream main

The previous revert removed __next.* metadata subdirectories from git
tracking entirely, but these directories exist on origin/main alongside
the flat .html files. Restore them via checkout from origin/main so the
PR diff only reflects actual code changes.

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix(a2a): drop dead headers option from discoverAgentCardCall

The backend /v1/a2a/discover endpoint no longer accepts a headers field
(removed in 78591b2 for SSRF safety), so any headers passed through
DiscoverAgentCardOptions were silently discarded by the API request
body. Remove the field and the conditional that copies it onto the
request body.

* fix(a2a): skip merge for non-A2A agents and align pydantic-ai result shape

The agent create/update/patch handlers ran the LiteLLM-fronting merge
unconditionally, so registrations that did not provide
agent_card_params still ended up with a synthesised card carrying
supportedInterfaces, securitySchemes, and default skills. Gate the
merge on a non-empty agent_card_params so plain chat/LLM agents stay
non-A2A in the registry.

Also move kind: 'message' inside the a2a_message dict in the Pydantic
AI non-streaming response so its construction matches the completion
bridge rather than spreading kind on top of a separate dict.

* Fix three bugs in A2A discovery flow

1. UI: Stabilize discoveryRequest deps to avoid redundant /v1/a2a/discover
   API calls. The parent rebuilds the discoveryRequest object on every form
   keystroke, so depend on primitive proxies (discovery_mode + serialized
   params) rather than the object identity. Read the actual object via a
   ref inside handleDiscover.

2. Backend: Route the well-known card fetch through async_safe_get so the
   admin /v1/a2a/discover endpoint can't be used to probe private/loopback
   addresses or cloud metadata endpoints. SSRFError is a separate handled
   case so it surfaces a clear AgentCardDiscoveryError.

3. Streaming: Make openai_chunk_to_a2a_chunk emit the same flat result
   shape as the non-streaming response (kind/role/parts/messageId at the
   result level), with envelope-level 'final' added. Matches the existing
   create_artifact_update_event pattern and lets consumers read a uniform
   result shape across streaming and non-streaming.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a/ui): include savedAgentCard in handleDiscover deps

The previous deps list omitted savedAgentCard, so handleDiscover (and
the resetSelections it calls) kept the closure's saved-card value even
after the parent refetched the agent. Clicking 'Re-discover' would
then pre-select skills against stale data. Adding savedAgentCard to
the deps array forces the callback to refresh whenever the saved card
changes.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): align pydantic-ai test + docstring with direct-Message result shape

The non-streaming A2A response was changed so that `result` is the Message
itself (kind="message"), per spec / SendMessageResponse. Update the
PydanticAITransformation._transform_to_a2a_response test and docstring that
still described the old `result.message` envelope so internal consumers
match the producer.

* fix(a2a): strip additionalInterfaces and let configured metadata win over A2A request

- merge_agent_card no longer carries upstream additionalInterfaces through;
  storing those alternate URLs would let authenticated agent callers reach
  the backend directly and bypass proxy auth/budget/logging.
- apply_forward_metadata_to_completion_params now layers client-supplied A2A
  metadata UNDER any agent-owner-configured extra_body.metadata, so server-set
  run metadata stays authoritative on key conflicts.

* fix(agents): merge agent card even when agent_card_params is an empty dict

Treat an explicitly provided empty agent_card_params ({}) as 'card
provided but empty' instead of 'no card', so the LiteLLM-fronting merge
still injects securitySchemes, supportedInterfaces, and protocolVersion.
Without this, the well-known endpoint could serve a bare card with only
a rewritten url, advertising no authentication to A2A clients.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* refactor(a2a): drop dead openai_chunk_to_a2a_chunk helper

The deprecated single-chunk helper has no callers anywhere in the
codebase — the streaming path emits proper A2A events via
create_task_event / create_status_update_event /
create_artifact_update_event in handler.py. Removing the dead method
also eliminates the inconsistency where the unused chunk inlined the
envelope-level final flag inside the Message result.

* fix(a2a): scope a2a lazy-feature so it doesn't subsume /v1/a2a/discover

- _lazy_features.py: use /a2a prefix + /message/send suffix for the
  a2a feature so a request to /v1/a2a/discover no longer triggers the
  a2a_endpoints module to load alongside a2a_registration.
- agent_endpoints/endpoints.py: drop the no-op description override
  kwarg from _build_merged_agent_card and its three call sites. The
  upstream card's description is already preserved by merge_agent_card's
  deepcopy, so passing it explicitly did nothing.

* style: black-format litellm/a2a_protocol/litellm_completion_bridge/transformation.py

* fix: address PR bugfix review for a2a discovery + metadata forwarding

- agent create form (add_agent_form.tsx): drop the skills.length > 0
  guard so an admin can clear all discovered skills during creation,
  matching the edit form's overlay behavior (consistency between
  create and edit flows).

- agent_card_discovery.tsx: stop including savedAgentCard in the
  handleDiscover useCallback deps. Read it via a ref inside
  resetSelections instead, so a parent-driven re-render that hands us
  a new savedAgentCard object reference (e.g. a background refresh of
  the agent record) does not recreate handleDiscover and re-fire the
  auto-discover effect, which would otherwise overwrite in-progress
  user edits in parent-driven mode (debounceMs = 0).

- a2a_endpoints.invoke_agent_a2a: skip 'metadata' when moving
  litellm params off of A2A MessageSendParams into body. The A2A
  protocol defines params.metadata as a first-class request-level
  field, and the completion bridge's get_forward_metadata is supposed
  to merge it with message.metadata. Previously the proxy always
  stripped params.metadata before constructing MessageSendParams, so
  the params-level branch in get_forward_metadata was dead code in
  the proxy flow.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): return 404 from get_agent_card when agent has no card

* fix(agents): apply discovery overlay uniformly on create and dedupe ALLOWED_CAPABILITY_KEYS

- buildAgentData now applies overlayDiscoveredCardParams after every
  non-custom branch (a2a, use_a2a_form_fields, dynamic) so types with
  credential_fields no longer silently drop discovered skills,
  capabilities, input/output modes, provider, and icon/doc URLs on
  submit. Mirrors the edit flow in agent_info.tsx.
- Export ALLOWED_CAPABILITY_KEYS from agent_discovery_utils and import
  it in agent_card_discovery so the rendering and selection-filtering
  logic share a single source of truth.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* ci(proxy-endpoints): wire tests/test_litellm/proxy/a2a into the shard

The two new test files (test_discovery.py, test_agent_card.py) were
not picked up by any pytest path, so their coverage never reached
codecov and patch coverage fell below the auto target.

* fix(ui): overlay discovered name/description in create flow for dynamic agents

Mirror the edit-form overlay in agent_info.tsx so dynamic agent types
(e.g. LangGraph) whose forms don't register name/description as
Form.Items don't silently lose those discovery-panel edits on save.

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): default merged agent card version, null-guard runtime URL lookup, scope discovery auto-fire to A2A types

- merge_agent_card now defaults version to 1.0.0 when upstream omits it
  (A2A v1.0 schema requires the field).
- invoke_agent_a2a guards against agent_card_params being None so plain
  chat agents routed via the A2A path return a JSON-RPC error instead of
  AttributeError.
- buildDiscoveryRequest no longer falls back to any URL-shaped credential
  field for non-A2A agent types (Azure AI Foundry, Bedrock AgentCore,
  Vertex). Discovery only auto-fires for pure A2A and use_a2a_form_fields
  runtimes; the manual URL input remains available as an escape hatch.

* fix(ui): extract overlayDiscoveredCardParams + debounce parent-driven discovery

Two findings from greptile review:

1. `overlayDiscoveredCardParams` was copy-pasted between `add_agent_form.tsx`
   and `agent_info.tsx`. Move it to `agent_discovery_utils.ts` so the create
   and edit flows share the same overlay logic and there's only one place to
   update when discovered fields change.

2. `agent_card_discovery.tsx` used a zero-debounce path for parent-driven
   mode, which fires one discovery HTTP request per keystroke when an admin
   types into the parent form's URL / api_base / assistant_id fields (the
   parent rebuilds the plan from watched form values every render). Apply
   the same 400ms debounce uniformly.

* fix(a2a): preserve discovery name edit, default discovery headers, sync url on re-discover

- _build_merged_agent_card: prefer card-supplied name over agent_name so
  the discovery panel's editable 'Name (shown to API clients)' value is
  not silently overwritten by the internal identifier.
- async_safe_get call in fetch_well_known_card: pass headers or {} to
  avoid TypeError({**None, 'Host': ...}) when URL validation is enabled
  in production (default).
- agent_info handleApplyDiscoveredCard: set url: selection.upstream_url
  in fieldsToSet so re-discovery during edit refreshes the form's URL
  field for pure A2A agents (matches add_agent_form).

Co-authored-by: Yassin Kortam <yassin@berri.ai>

* fix(a2a): scrub upstream url from /public/agent_hub cards

Public agent_hub returned agent_card_params verbatim, exposing the
retained upstream backend url to unauthenticated callers. Rewrite the
url to the proxy /a2a/{agent_id} entrypoint on response, matching the
behavior of the authenticated well-known agent-card endpoint, so the
backend cannot be reached outside LiteLLM's auth, budget, and logging
path.

* fix(a2a): include suffix-matched routes in lazy warm openapi fragment

---------

Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: Yassin Kortam <yassin@berri.ai>
Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
2026-05-29 20:50:42 -07:00
.circleci feat(guardrails): add Microsoft Purview DLP guardrail (#24966) 2026-05-22 15:59:04 -07:00
.devcontainer build: migrate packaging, CI, and Docker from Poetry to uv (#25007) 2026-04-09 11:46:23 -07:00
.github feat(a2a): well-known agent-card discovery + LangGraph Platform mode (#28860) 2026-05-29 20:50:42 -07:00
.semgrep/rules security: remove .claude/settings.json and add semgrep rule to prevent re-adding 2026-03-25 11:57:43 -07:00
backend fix(docker): use system Node in componentized builders + retry apk add (#28888) 2026-05-26 15:41:38 -07:00
ci_cd Drop dep bumps + black-26 reformat to clear fork CI policy 2026-05-07 23:04:52 +00:00
cookbook chore(cookbook): bump Go directive to 1.26.3 in gollem example (#29234) 2026-05-28 18:12:31 -07:00
db_scripts Drop dep bumps + black-26 reformat to clear fork CI policy 2026-05-07 23:04:52 +00:00
deploy Litellm oss staging 250526 (#28770) 2026-05-26 11:57:39 -07:00
dist build: update dependencies 2025-11-01 12:58:39 -07:00
docker chore(admin-ui): regenerate static export with trailingSlash: true (#28112) 2026-05-25 21:06:50 -07:00
docs fix(hosted_vllm): normalize custom tools for chat completions (#25763) 2026-05-05 17:27:02 -07:00
enterprise fix(bedrock): support tool search results + chat annotations (#29120) 2026-05-29 20:48:36 -07:00
gateway fix(docker): use system Node in componentized builders + retry apk add (#28888) 2026-05-26 15:41:38 -07:00
helm/litellm feat(helm): split per-component ServiceAccounts for gateway, backend, and UI (#28712) 2026-05-28 13:20:53 -07:00
litellm feat(a2a): well-known agent-card discovery + LangGraph Platform mode (#28860) 2026-05-29 20:50:42 -07:00
litellm-proxy-extras chore(ci): bump versions (#28287) 2026-05-19 15:10:37 -07:00
migrations fix(docker): use system Node in componentized builders + retry apk add (#28888) 2026-05-26 15:41:38 -07:00
scripts fix: improve bedrock streaming hot path perf (#28720) 2026-05-28 11:31:37 -07:00
terraform/litellm feat: add Terraform stacks for deploying LiteLLM on AWS and GCP (#27673) 2026-05-16 17:26:20 -07:00
tests feat(a2a): well-known agent-card discovery + LangGraph Platform mode (#28860) 2026-05-29 20:50:42 -07:00
ui feat(a2a): well-known agent-card discovery + LangGraph Platform mode (#28860) 2026-05-29 20:50:42 -07:00
.dockerignore fix critical CVE vulnerabliltes (#20683) 2026-02-07 22:23:01 -08:00
.env.example Add new model provider Novita AI (#7582) (#9527) 2025-05-12 21:49:30 -07:00
.flake8 chore: list all ignored flake8 rules explicit 2023-12-23 09:07:59 +01:00
.git-blame-ignore-revs Add my commit to .git-blame-ignore-revs 2024-05-12 10:21:10 -07:00
.gitattributes
.gitguardian.yaml build: migrate packaging, CI, and Docker from Poetry to uv (#25007) 2026-04-09 11:46:23 -07:00
.gitignore feat: add Terraform stacks for deploying LiteLLM on AWS and GCP (#27673) 2026-05-16 17:26:20 -07:00
.npmrc [Fix] CI/Tooling: Correct min-release-age value in .npmrc files 2026-04-29 19:49:27 -07:00
AGENTS.md docs: hand-written CLAUDE.md; point GEMINI.md and AGENTS.md at it (#29252) 2026-05-29 00:05:05 -07:00
ARCHITECTURE.md [Docs] Litellm architecture fixes 2 (#19252) 2026-01-16 14:52:16 -08:00
CLAUDE.md docs: hand-written CLAUDE.md; point GEMINI.md and AGENTS.md at it (#29252) 2026-05-29 00:05:05 -07:00
codecov.yaml fix(ci): flag codecov uploads, enable carryforward, close coverage gaps (#28028) 2026-05-16 10:56:32 -07:00
CONTRIBUTING.md build: migrate packaging, CI, and Docker from Poetry to uv (#25007) 2026-04-09 11:46:23 -07:00
cosign.pub [Infra] Add release workflow and cosign public key 2026-03-31 14:30:27 -07:00
docker-compose.hardened.yml [Feature] Download Prisma binaries at build time instead of at runtime for Security Restricted environments (#17695) 2025-12-16 21:25:53 +05:30
docker-compose.yml feat: add read-replica routing for Prisma DB via DATABASE_URL_READ_REPLICA (#27493) 2026-05-08 21:05:50 -07:00
Dockerfile fix(docker): restore npm@11.14.0 lost in merge resolution 2026-05-07 17:25:10 -07:00
GEMINI.md docs: hand-written CLAUDE.md; point GEMINI.md and AGENTS.md at it (#29252) 2026-05-29 00:05:05 -07:00
LICENSE refactor: creating enterprise folder 2024-02-15 12:54:13 -08:00
license_cache.json Add granian as a ASGI compliant web server. Provider better throughput stability, (#26027) 2026-05-21 19:08:37 -07:00
Makefile tests(vcr): trim non-load-bearing comments and docstrings 2026-04-30 21:48:48 +00:00
mcp_servers.json Add ScrapeGraph MCP server configuration (#18923) 2026-01-11 21:57:46 +05:30
model_prices_and_context_window.json feat(anthropic): add Claude Opus 4.8 and prune reasoning-effort flags (#29238) 2026-05-28 18:50:33 -07:00
package-lock.json chore(deps): refresh dependency locks 2026-05-04 11:36:18 -07:00
package.json chore(deps): refresh dependency locks 2026-05-04 11:36:18 -07:00
policy_templates.json feat: Add Canadian PII protection (PIPEDA) (#22951) 2026-03-06 18:27:31 -08:00
prometheus.yml build(docker-compose.yml): add prometheus scraper to docker compose 2024-07-24 10:09:23 -07:00
provider_endpoints_support.json Litellm oss staging 04 21 2026 2 (#26569) 2026-05-20 21:25:19 -07:00
proxy_server_config.yaml chore(ci): modernize model references in tests and configs (#27856) 2026-05-15 15:44:28 -07:00
pyproject.toml chore(ci): bump version (#29242) 2026-05-28 18:49:04 -07:00
pyrightconfig.json Agents - support agent registration + discovery (A2A spec) (#16615) 2025-11-14 18:23:30 -08:00
README.md Litellm oss staging (#28161) 2026-05-18 16:27:44 -07:00
render.yaml build(render.yaml): fix health check route 2024-05-24 09:45:28 -07:00
ruff.toml [Fix] CI: fix 6 more CircleCI job failures from uv migration 2026-04-10 21:06:25 -07:00
schema.prisma Litellm oss staging (#28161) 2026-05-18 16:27:44 -07:00
security.md chore: update security.md (#24871) 2026-03-31 13:13:18 -07:00
taplo.toml fix(agentcore): simplify agentcore streaming (#17141) 2026-01-19 05:20:24 -08:00
uv.lock chore(ci): bump version (#29242) 2026-05-28 18:49:04 -07:00

🚅 LiteLLM

LiteLLM AI Gateway

Open Source AI Gateway for 100+ LLMs. Self-hosted. Enterprise-ready. Call any LLM in OpenAI format.

Deploy to Render Deploy on Railway

LiteLLM Proxy Server (AI Gateway) | Hosted Proxy | Enterprise Tier | Website

PyPI Version GitHub Stars Y Combinator W23 Whatsapp Discord Slack CodSpeed

Group 7154 (1)

What is LiteLLM

LiteLLM is an open source AI Gateway that gives you a single, unified interface to call 100+ LLM providers — OpenAI, Anthropic, Gemini, Bedrock, Azure, and more — using the OpenAI format.

Use it as a Python SDK for direct library integration, or deploy the AI Gateway (Proxy Server) as a centralized service for your team or organization.

Jump to LiteLLM Proxy (LLM Gateway) Docs
Jump to Supported LLM Providers


Why LiteLLM

Managing LLM calls across providers gets complicated fast — different SDKs, auth patterns, request formats, and error types for every model. LiteLLM removes that friction:

  • Unified API — one interface for 100+ LLMs, no provider-specific SDK juggling
  • Drop-in OpenAI compatibility — swap providers without rewriting your code
  • Production-ready gateway — virtual keys, spend tracking, guardrails, load balancing, and an admin dashboard out of the box
  • 8ms P95 latency at 1k RPS (benchmarks)

OSS Adopters

Stripe image Google ADK Greptile OpenHands

Netflix

OpenAI Agents SDK

Features

LLMs - Call 100+ LLMs (Python SDK + AI Gateway)

All Supported Endpoints - /chat/completions, /responses, /embeddings, /images, /audio, /batches, /rerank, /a2a, /messages and more.

Python SDK

uv add litellm
from litellm import completion
import os

os.environ["OPENAI_API_KEY"] = "your-openai-key"
os.environ["ANTHROPIC_API_KEY"] = "your-anthropic-key"

# OpenAI
response = completion(model="openai/gpt-4o", messages=[{"role": "user", "content": "Hello!"}])

# Anthropic  
response = completion(model="anthropic/claude-sonnet-4-20250514", messages=[{"role": "user", "content": "Hello!"}])

AI Gateway (Proxy Server)

Getting Started - E2E Tutorial - Setup virtual keys, make your first request

uv tool install 'litellm[proxy]'
litellm --model gpt-4o
import openai

client = openai.OpenAI(api_key="anything", base_url="http://0.0.0.0:4000")
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Hello!"}]
)

Docs: LLM Providers

Agents - Invoke A2A Agents (Python SDK + AI Gateway)

Supported Providers - LangGraph, Vertex AI Agent Engine, Azure AI Foundry, Bedrock AgentCore, Pydantic AI

Python SDK - A2A Protocol

from litellm.a2a_protocol import A2AClient
from a2a.types import SendMessageRequest, MessageSendParams
from uuid import uuid4

client = A2AClient(base_url="http://localhost:10001")

request = SendMessageRequest(
    id=str(uuid4()),
    params=MessageSendParams(
        message={
            "role": "user",
            "parts": [{"kind": "text", "text": "Hello!"}],
            "messageId": uuid4().hex,
        }
    )
)
response = await client.send_message(request)

AI Gateway (Proxy Server)

Step 1. Add your Agent to the AI Gateway

Step 2. Call Agent via A2A SDK

from a2a.client import A2ACardResolver, A2AClient
from a2a.types import MessageSendParams, SendMessageRequest
from uuid import uuid4
import httpx

base_url = "http://localhost:4000/a2a/my-agent"  # LiteLLM proxy + agent name
headers = {"Authorization": "Bearer sk-1234"}    # LiteLLM Virtual Key

async with httpx.AsyncClient(headers=headers) as httpx_client:
    resolver = A2ACardResolver(httpx_client=httpx_client, base_url=base_url)
    agent_card = await resolver.get_agent_card()
    client = A2AClient(httpx_client=httpx_client, agent_card=agent_card)

    request = SendMessageRequest(
        id=str(uuid4()),
        params=MessageSendParams(
            message={
                "role": "user",
                "parts": [{"kind": "text", "text": "Hello!"}],
                "messageId": uuid4().hex,
            }
        )
    )
    response = await client.send_message(request)

Docs: A2A Agent Gateway

MCP Tools - Connect MCP servers to any LLM (Python SDK + AI Gateway)

Python SDK - MCP Bridge

from mcp import ClientSession, StdioServerParameters
from mcp.client.stdio import stdio_client
from litellm import experimental_mcp_client
import litellm

server_params = StdioServerParameters(command="python", args=["mcp_server.py"])

async with stdio_client(server_params) as (read, write):
    async with ClientSession(read, write) as session:
        await session.initialize()

        # Load MCP tools in OpenAI format
        tools = await experimental_mcp_client.load_mcp_tools(session=session, format="openai")

        # Use with any LiteLLM model
        response = await litellm.acompletion(
            model="gpt-4o",
            messages=[{"role": "user", "content": "What's 3 + 5?"}],
            tools=tools
        )

AI Gateway - MCP Gateway

Step 1. Add your MCP Server to the AI Gateway

Step 2. Call MCP tools via /chat/completions

curl -X POST 'http://0.0.0.0:4000/v1/chat/completions' \
  -H 'Authorization: Bearer sk-1234' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role": "user", "content": "Summarize the latest open PR"}],
    "tools": [{
      "type": "mcp",
      "server_url": "litellm_proxy/mcp/github",
      "server_label": "github_mcp",
      "require_approval": "never"
    }]
  }'

Use with Cursor IDE

{
  "mcpServers": {
    "LiteLLM": {
      "url": "http://localhost:4000/mcp/",
      "headers": {
        "x-litellm-api-key": "Bearer sk-1234"
      }
    }
  }
}

Docs: MCP Gateway

Supported Providers (Website Supported Models | Docs)

Provider /chat/completions /messages /responses /embeddings /image/generations /audio/transcriptions /audio/speech /moderations /batches /rerank
Abliteration (abliteration) ✅
AI/ML API (aiml) ✅ ✅ ✅ ✅ ✅
AI21 (ai21) ✅ ✅ ✅
AI21 Chat (ai21_chat) ✅ ✅ ✅
Aleph Alpha ✅ ✅ ✅
Amazon Nova ✅ ✅ ✅
Anthropic (anthropic) ✅ ✅ ✅ ✅
Anthropic Text (anthropic_text) ✅ ✅ ✅ ✅
Anyscale ✅ ✅ ✅
AssemblyAI (assemblyai) ✅ ✅ ✅ ✅
Auto Router (auto_router) ✅ ✅ ✅
AWS - Bedrock (bedrock) ✅ ✅ ✅ ✅ ✅
AWS - Sagemaker (sagemaker) ✅ ✅ ✅ ✅
Azure (azure) ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅
Azure AI (azure_ai) ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅
Azure Text (azure_text) ✅ ✅ ✅ ✅ ✅ ✅ ✅
Baseten (baseten) ✅ ✅ ✅
Bytez (bytez) ✅ ✅ ✅
Cerebras (cerebras) ✅ ✅ ✅
Clarifai (clarifai) ✅ ✅ ✅
Cloudflare AI Workers (cloudflare) ✅ ✅ ✅
Codestral (codestral) ✅ ✅ ✅
Cohere (cohere) ✅ ✅ ✅ ✅ ✅
Cohere Chat (cohere_chat) ✅ ✅ ✅
CometAPI (cometapi) ✅ ✅ ✅ ✅
CompactifAI (compactifai) ✅ ✅ ✅
Custom (custom) ✅ ✅ ✅
Custom OpenAI (custom_openai) ✅ ✅ ✅ ✅ ✅ ✅ ✅
Dashscope (dashscope) ✅ ✅ ✅ ✅ ✅
Databricks (databricks) ✅ ✅ ✅
DataRobot (datarobot) ✅ ✅ ✅
Deepgram (deepgram) ✅ ✅ ✅ ✅
DeepInfra (deepinfra) ✅ ✅ ✅
Deepseek (deepseek) ✅ ✅ ✅
ElevenLabs (elevenlabs) ✅ ✅ ✅ ✅ ✅
Empower (empower) ✅ ✅ ✅
Fal AI (fal_ai) ✅ ✅ ✅ ✅
Featherless AI (featherless_ai) ✅ ✅ ✅
Fireworks AI (fireworks_ai) ✅ ✅ ✅
FriendliAI (friendliai) ✅ ✅ ✅
Galadriel (galadriel) ✅ ✅ ✅
GitHub Copilot (github_copilot) ✅ ✅ ✅ ✅
GitHub Models (github) ✅ ✅ ✅
Google - PaLM ✅ ✅ ✅
Google - Vertex AI (vertex_ai) ✅ ✅ ✅ ✅ ✅
Google AI Studio - Gemini (gemini) ✅ ✅ ✅
GradientAI (gradient_ai) ✅ ✅ ✅
Groq AI (groq) ✅ ✅ ✅
Heroku (heroku) ✅ ✅ ✅
Hosted VLLM (hosted_vllm) ✅ ✅ ✅
Huggingface (huggingface) ✅ ✅ ✅ ✅ ✅
Hyperbolic (hyperbolic) ✅ ✅ ✅
IBM - Watsonx.ai (watsonx) ✅ ✅ ✅ ✅
Infinity (infinity) ✅
Jina AI (jina_ai) ✅
Lambda AI (lambda_ai) ✅ ✅ ✅
Lemonade (lemonade) ✅ ✅ ✅
LiteLLM Proxy (litellm_proxy) ✅ ✅ ✅ ✅ ✅
Llamafile (llamafile) ✅ ✅ ✅
LM Studio (lm_studio) ✅ ✅ ✅
Maritalk (maritalk) ✅ ✅ ✅
Meta - Llama API (meta_llama) ✅ ✅ ✅
Mistral AI API (mistral) ✅ ✅ ✅ ✅
Moonshot (moonshot) ✅ ✅ ✅
Morph (morph) ✅ ✅ ✅
Nebius AI Studio (nebius) ✅ ✅ ✅ ✅
NLP Cloud (nlp_cloud) ✅ ✅ ✅
Novita AI (novita) ✅ ✅ ✅
Nscale (nscale) ✅ ✅ ✅
Nvidia NIM (nvidia_nim) ✅ ✅ ✅
OCI (oci) ✅ ✅ ✅
Ollama (ollama) ✅ ✅ ✅ ✅
Ollama Chat (ollama_chat) ✅ ✅ ✅
Oobabooga (oobabooga) ✅ ✅ ✅ ✅ ✅ ✅ ✅
OpenAI (openai) ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅ ✅
OpenAI-like (openai_like) ✅
OpenRouter (openrouter) ✅ ✅ ✅
OVHCloud AI Endpoints (ovhcloud) ✅ ✅ ✅
Perplexity AI (perplexity) ✅ ✅ ✅
Petals (petals) ✅ ✅ ✅
Predibase (predibase) ✅ ✅ ✅
Recraft (recraft) ✅
Replicate (replicate) ✅ ✅ ✅
Sagemaker Chat (sagemaker_chat) ✅ ✅ ✅
Sambanova (sambanova) ✅ ✅ ✅
Snowflake (snowflake) ✅ ✅ ✅
Text Completion Codestral (text-completion-codestral) ✅ ✅ ✅
Text Completion OpenAI (text-completion-openai) ✅ ✅ ✅ ✅ ✅ ✅ ✅
Together AI (together_ai) ✅ ✅ ✅
Topaz (topaz) ✅ ✅ ✅
Triton (triton) ✅ ✅ ✅
V0 (v0) ✅ ✅ ✅
Vercel AI Gateway (vercel_ai_gateway) ✅ ✅ ✅
VLLM (vllm) ✅ ✅ ✅
Volcengine (volcengine) ✅ ✅ ✅
Voyage AI (voyage) ✅
WandB Inference (wandb) ✅ ✅ ✅
Watsonx Text (watsonx_text) ✅ ✅ ✅
xAI (xai) ✅ ✅ ✅
Xinference (xinference) ✅

Read the Docs


Get Started

You can use LiteLLM through either the Proxy Server or Python SDK. Both give you a unified interface to access multiple LLMs (100+ LLMs). Choose the option that best fits your needs:

LiteLLM AI Gateway LiteLLM Python SDK
Use Case Central service (LLM Gateway) to access multiple LLMs Use LiteLLM directly in your Python code
Who Uses It? Gen AI Enablement / ML Platform Teams Developers building LLM projects
Key Features Centralized API gateway with authentication and authorization, multi-tenant cost tracking and spend management per project/user, per-project customization (logging, guardrails, caching), virtual keys for secure access control, admin dashboard UI for monitoring and management Direct Python library integration in your codebase, Router with retry/fallback logic across multiple deployments (e.g. Azure/OpenAI) - Router, application-level load balancing and cost tracking, exception handling with OpenAI-compatible errors, observability callbacks (Lunary, MLflow, Langfuse, etc.)

Stable Release: Use docker images with the -stable tag. These have undergone 12 hour load tests, before being published. More information about the release cycle here

Support for more providers. Missing a provider or LLM Platform, raise a feature request.

Run in Developer Mode

Services

  1. Setup .env file in root
  2. Run dependant services docker-compose up db prometheus

Backend

  1. (In root) create virtual environment python -m venv .venv
  2. Activate virtual environment source .venv/bin/activate
  3. Install dependencies uv sync --all-extras --group proxy-dev
  4. uv run prisma generate
  5. prisma generate
  6. Start proxy backend python litellm/proxy/proxy_cli.py

Frontend

  1. Navigate to ui/litellm-dashboard
  2. Install dependencies npm install
  3. Run npm run dev to start the dashboard

Verify Docker Image Signatures

All LiteLLM Docker images published to GHCR are signed with cosign. Every release is signed with the same key introduced in commit 0112e53.

Verify using the pinned commit hash (recommended):

A commit hash is cryptographically immutable, so this is the strongest way to ensure you are using the original signing key:

cosign verify \
  --key https://raw.githubusercontent.com/BerriAI/litellm/0112e53046018d726492c814b3644b7d376029d0/cosign.pub \
  ghcr.io/berriai/litellm:<release-tag>

Verify using a release tag (convenience):

Tags are protected in this repository and resolve to the same key. This option is easier to read but relies on tag protection rules:

cosign verify \
  --key https://raw.githubusercontent.com/BerriAI/litellm/<release-tag>/cosign.pub \
  ghcr.io/berriai/litellm:<release-tag>

Replace <release-tag> with the version you are deploying (e.g. v1.83.0-stable).


Enterprise

For companies that need better security, user management and professional support

Get an Enterprise License Talk to founders

This covers:

  • ✅ Features under the LiteLLM Commercial License:
  • ✅ Feature Prioritization
  • ✅ Custom Integrations
  • ✅ Professional Support - Dedicated discord + slack
  • ✅ Custom SLAs
  • ✅ Secure access with Single Sign-On

Contributing

We welcome contributions to LiteLLM! Whether you're fixing bugs, adding features, or improving documentation, we appreciate your help.

Quick Start for Contributors

This requires uv to be installed.

git clone https://github.com/BerriAI/litellm.git
cd litellm
make install-dev    # Install development dependencies
make format         # Format your code
make lint           # Run all linting checks
make test-unit      # Run unit tests
make format-check   # Check formatting only

For detailed contributing guidelines, see CONTRIBUTING.md.

📖 Contributing to documentation? The LiteLLM docs have moved to a separate repository: BerriAI/litellm-docs. Please open doc PRs there. Docs are served at docs.litellm.ai.

Code Quality / Linting

LiteLLM follows the Google Python Style Guide.

Our automated checks include:

  • Black for code formatting
  • Ruff for linting and code quality
  • MyPy for type checking
  • Circular import detection
  • Import safety checks

All these checks must pass before your PR can be merged.

Support / talk with founders

Contributors